Network Printer

Abstract

A network printer includes a communication unit that conducts communication with a communication terminal connected through a network, and a recording unit. The recording unit can be put in a first power state and a second power state, whose power consumption is lower than that of the first power state, and the recording unit records print data received from the communication unit during the first power state. The communication unit includes a confirmation signal delivery unit that sends a connection confirmation signal to the communication terminal when the print data is not successively received from the communication terminal for a first predetermined time while a session is established and a transition unit that causes the power state of the recording unit to transition to the second power state when a reply to the connection confirmation signal has not been successively received for a second predetermined time.

1 . A network printer comprising:
 a communication unit that conducts communication with a communication terminal connected through a network; and   a recording unit having a first power state and a second power state, power consumption of the second power state being lower than that of the first power state, the recording unit recording print data received from the communication unit onto a sheet when being in the first power state, wherein   the communication unit includes:   a confirmation signal delivery unit that sends a connection confirmation signal to the communication terminal when the print data is not successively received from the communication terminal for a first predetermined time while a session is established; and   a transition unit that causes the power state of the recording unit to transition to the second power state when a reply to the connection confirmation signal is not successively received for a second predetermined time after the confirmation signal delivery unit sends the connection confirmation signal.   
     
     
         2 . The network printer according to  claim 1 , wherein
 the recording unit includes:   a printer controller that expands the print data described in a page description language into raster data;   a printer engine that records the raster data onto the sheet; and   a control unit that controls the printer engine, and   the communication unit aborts processing of conducting communication with the communication terminal and the transition unit causes the respective power state of the printer controller, the printer engine, and the control unit to transition to the second power state, when a reply to the connection confirmation signal is not successively received for the second predetermined time.   
     
     
         3 . The network printer according to  claim 1 , wherein
 the communication unit includes a PHY unit that performs conversion between a logic signal and an electric signal, and   the confirmation signal delivery unit sends the connection confirmation signal when the PHY unit is in a link-up state.   
     
     
         4 . The network printer according to  claim 3 , wherein
 a session with the communication terminal is released and the transition unit causes the power state of the recording unit to transition to the second power state, when the PHY unit is not in the link-up state.   
     
     
         5 . The network printer according to  claim 1 , wherein
 the confirmation signal delivery unit sends the connection confirmation signal to the communication terminal, when a reply to the connection confirmation signal is received before the second predetermined time elapses since the connection confirmation signal is sent, and when the print data is not successively received for a time longer than the first predetermined time.   
     
     
         6 . The network printer according to  claim 1 , wherein
 the connection confirmation signal is an ARP or a ping.   
     
     
         7 . The network printer according to  claim 2 , wherein
 the communication unit notifies the printer controller of information indicating an end of reception when processing of receiving the print data transmitted from the communication terminal is normally ended,   the printer controller notifies the control unit of information indicating an end of the expanding processing and transitions to the second power state when the expansion of the print data is ended, and   the control unit notifies the communication unit of information indicating an end of the recording processing and transitions to the second power state when the printer engine ends the recording of the print data.   
     
     
         8 . The network printer according to  claim 1 , wherein
 the communication unit further includes a temperature control unit that performs temperature control such that a temperature at the recording unit becomes a predetermined temperature or less after the power state of the recording unit transitions to the second power state.   
     
     
         9 . The network printer according to  claim 1 , wherein
 when the communication unit receives the print data from the communication terminal, after a session is established with the communication terminal, a session establishment request received from the communication terminal is analyzed and an IP address or a MAC address of the communication terminal is extracted.